Venetian blind having tilt-limiting attachment

ABSTRACT

The head of the blind is provided with a two-part attachment which serves to limit the tilting movement of the slats. For a different limit of forward and/or backward tilt, one part of the attachment is replaced by a part which is similar but which establishes the different limit or limits.

United States Paten [191 Anderle et al.

[ 1 Aug. 13, 1974 VENETIAN BLIND HAVING TILT-LIMITING ATTACHMENT [75] Inventors: Joseph A. Anderle, Clifton; George Neira, Teaneck, both of NJ.

[73] Assignee: Levolor Lorentzen, Inc., Hoboken,

[22] Filed: Mar. 8, 1973 [21] Appl. No.: 339,245

52 us. Cl. .Q 160/176- [51'] Int. Cl D0611 9/26, E06b 9/307 [58] Field of Search ..t 160/166-178 [56] References Cited UNITED STATES PATENTS Trinkaus 160/176 1,687,092 10/1928 Hough 160/176 Primary Examiner-Peter M. Caun' Attorney, Agent, or FirmCharles F. Chisholm 57 ABSTRACT The head of the blind is provided with a two-part attachment which serves to limit the tilting movement of the slats. For a different limit of forward and/0r backward tilt, one part of the attachment is replaced by a part which is similar but which establishes the different limit or limits.

9 Claims, 11 Drawing Figures Pmmim m w I 3.828.838

SHEET 1 0f 2 VENETIAN BLIND HAVING TILT-LIMITING ATTACHMENT BACKGROUND OF THE INVENTION A Venetian blind commonly has a ladder-and-slat assembly which is usually suspended in a vertical plane at a window opening. Those edges of the slats which are toward the inside of the building will be considered to be the front edges, and those edges which are toward the outside of the building will be considered to be the rear edges. To tilt the slats forwardly (front edges depressed), the front sidepieces of the ladders are lowelongated sheet-steel channel-and parts that are affixed t the channel. Such parts are mostly within the channel and include a cord lock, a tilter, a tilt bar, and rockers or drumsthat are mounted on the tilt bar. The upper ends of the sidepieces of the ladders are attached to the rockers or drums whereby the ladder-and-slat as sembly is supported by the tilt bar, and the slats are tilted when rotative movement is imparted to the tilt bar, all as is well understood.

The tilter of a Venetian blind customarilyaffords full tilting movement of the slats, i.e., forward tilt of close to 90 and rearward tilt of close to 90, which adds up to a tilting range of close to 180. When a Venetian blind is installed in a particular building, or in a particular location in the building, it is often desired to establish predetermined limits of slat-tilt which in one or both directions are less than the tilt afforded by the tilter. The reasons for establishing such predetermined limits are varied,.and the limits themselves are selected according to the maximum forward and rearward tilts desired.

Among the reasons for establishing predetermined limits of tilt of the slats are: Some buildings object to the external appearance that is produced by different blinds in the bulding being left standing at widely different tilts. When a blind has highly reflecting slats,some angles of tilt in some locations at some times of day can cause objectionable glarein the window of an adjoining bulding. A fully closed blind can cause undesirable thermal effects in some circumstances, and the thermal effects may lead to breakage. of the window glass.

For the foregoing and'otherreasons it is desirable to be able to readily establish predetermined limits of tilt which, as regards forward and/or backward tilt, are less than the tilt that is afforded by the tilter. Also it is desirable that it be easy to change the predetermined limits, and be easy to eliminate them altogether.

SUMMARY OF THE INVENTION In the Venetian blind of the present invention the head of the blind is provided with an attachment which limits the rotative movement of the tilt bar to an amount that is less than the rotative movement afforded by the tilter. Thus the attachment serves to limit the tilting movement of the slats to an amount which is less than the tilting movement afforded by the tilter itself.

The present invention affords the following features, among others: (a) an attachment which can be applied readily to the head of the blind, (b) an attachment which can be removed readily from the head of the blind, (c) an attachment having a part which is replaceable readily with a similar part that establishes a different limit of tilt in one or both directions, (d) an attachment which has a stop member that is applied to the head and a cooperating limit member which is applied to the tilt bar of the head, (e) an attachment in which the limit member that is applied to the tilt bar is replaceable readily with a limit member which provides a different limit of tilt of the slats in one or both directions,.(f) an attachment in which the limit member is adjacent to the tilter and the stop member has a body portion which is between the tilter and an upstanding wall of the head channel, (g) an attachment in which the limit member is telescoped onto the tilt bar and is located adjacent to the tilter, and the stop member has a portion which extends alongside the limit member and retains the limit member adjacent to the tilter, (h) an attachment in which the stop member has a body portion that is between the tilter and the rear wall of I the head channel and the body has portions that extend alongside the two sides of the tilter which face toward the two ends of the channel, respectively, (i) an attachment in which the stop member is provided with a latch which engages beneath an inturned edge of the head channel, (j) an attachment in which the stop member is removable by springing the inturned edge of the head channel out of holding engagement with the latch of the stop member, and (R) an attachment in which the parts thereof are of stamped sheet-steel.

The presently preferred embodiment of the invention includes all of the foregoing features and affords additional features and aspects which will be apparent from the drawing and the description in connection therewith. As regards all of the same, it is left to the user of the invention to decide upon the omission of any features or aspects that are not needed for his particular purpose.

BRIEF DESCRIPTION OF THE DRAWING, OF WHICH THERE ARE TWO SHEETS FIG. 1 is a top plan view, with parts broken away, showing primarily the head of a Venetian blind before the tilt-limiting attachment has been applied.

FIG. 2 is a fragmentary exploded view, in isometric perspective, indicating the procedure for applying the attachment to the head of the blind.

FIG. 3 is a fragmentary top plan view showing the head of the blind with the attachment applied to the head.

FIG. 4 is a fragmentary end elevation of the blind as it would be seen when looking from the left of FIG. 1, but with the'head in section as indicated generally by the line 4-4 in FIG. 3.

FIGS. 5-11 are diagrams which show limit members that establish different pairs of tilting-limits for the slats, a pair of limits being composed of a forward limit and a rearward limit. Each figure indicates the maximum forward tilt (if any) of the slat and also the maximum rearward tilt (if any) of the slat.

DESCRIPTION OF THE PRESENTLY-PREFERRED EMBODIMENT OF THE INVENTION The drawing shows the presently-preferred embodiment of the invention, i.e., the best mode thus farcontemplated of carrying out the invention. Except as may be otherwise indicated, the description hereinafter (prior to the claims) refers to the particular form of the invention that is shown in the drawing and does not necessarily refer to any other form. The disclosure is by way of illustration and example, and the claims embrace other forms in which the invention may be embodied.

The Venetian blind and/or the parts thereof shown in FIGS. 1-4 will first be described without reference to the tilt-limiting attachment.

A ladder-and-slat assembly (FIG. 4) that is designated as a whole by is positioned beneath a head which is designated as a whole by 16. The ladder-andslat assembly includes a series of slats 17 (three shown) that are supported and articulated together in known manner by two or more ladders 18 (one shown). Each ladder 18 has a front sidepiece 18a and a rear sidepiece 18b, the two sidepieces being interconnected by vertically spaced crosspieces or rungs 18c on which the slats 17 rest.

The head 16 consists primarily of a sheet-steel channel 20 and the mechanism that is contained therein. The head channel 20 has a front wall 20a, a rear wall 20b and a bottom wall 200. Along the upper edge of each of the front and rear walls 200 and 20b there is a longitudinally-extending flangeor edge 20d which is folded inwardly and downwardly. The bottom wall 20c is pierced in known manner for the passage into the channel 20 of each sidepiece 18a and 18b of the ladders and each lift cord 22 (one shown).

A steel tilt bar 24 of D-shaped cross section is journalled in two or more cradles 26 (one shown, FIG. 1). Each cradle 26 is a l-piece sheet-steel stamping, having a base 26a from which spaced legs 26b and'26c extend vertically upwardly. Each leg is formed with a semicylindrical bearing at b in which the tilt bar 24 is journalled. The vertical leg 260 is provided with an arm 26d which has two fingers 26e and 26f. The arm 26d initially projects perpendicularly to the tilt bar 24 and the fingers 26e and 26f initially project parallel to the tilt bar 24. The cradle 26 that is shown is adjacent to the right-hand end of the tilt bar. The arm 26d has been bent as a whole 90 counterclockwise from its initial position; this disposes the finger 262 above the 'tilt bar 24 to hold it in the bearings at b, and disposes the finger 26f across the end of the tilt bar to act as a stop which limits longitudinal movement of the tilt bar to the right in FIG. 1. For a better understanding of the arm 26d, see FIG. 6 of U.S. Pat. No. 3,425,479 which shows the arm in elevation before it is bent.

The base 26a of the cradle rests against the bottomv 200 of the head channel and is secured thereto in any suitable manner. The base 26a is provided with a central hole 26h which registers with a hole (not shown) in the bottom 200 of the head channel to afford vertical passage of the lift cord 22 (FIG. 4). Midway between 18. At each cradle 26 the tilt bar 24-is provided with a drum-shaped rocker 27, which is a one-piece sheetsteel stamping that substantially spans the space between the legs 26b and 260 of the cradle.

The drawing shows the rocker 27 in mid position, i.e., in the position corresponding to the slats l7 of the blind (FIG. 4) having no tilt. With the rocker in the mid position as shown, the rocker hole 27d'is at the front and the rocker hole 27e is at the rear. The front sidepiece 18a of the ladder comes up through the hole 26j in the base of the cradle, extends across the top of the rocker, thence into the hole 27e in the rear of the rocker, and is secured to the rocker on the inside thereof. Conversely the rear sidepiece 18b of the ladder comes up through the hole 26k in the base of the cradle, extends across the top of the rocker, thence into the hole 27d in the front of the rocker, and is secured to the rocker on the inside thereof.

- The tilter, which is designated as a whole by 30, is assembled from six pieces. Four of the pieces are sheetsteel stampin gs which provide a boxlike hollow housing. The housing has a top 30a, a bottom (not shown), a side 30b which faces one end'of thehead channel 20, and a side 300 which faces the other end of the head channel. Extending integrally in opposite directions from the bottom edges of the sides 30b and 30c there are horizontal feet 31a and 32a, respectively, which rest against and are suitably secured to the bottom 20c of the head channel. The sides 30b and 300 of the tilter housing are pierced and formed with integral short thimbles 31d and 32a; these thimbles are coaxial .with the cradle bearing at b, and they constitute bearings for the projecting hubs 36a and 36b of a gear (not shown). The gear is axially pierced and rotates the D-shaped tilt bar 24 which passes through it. The body of the gear is provided with teeth which extend for 360 around its circumference and which mate with a double-thread worm35a (FIGS. 1 and 3). a The vworm 35a is part of a molded plastic piece which is designated as a whole by 35 in FIG. 4. The plastic piece includes a worm shaft 350 which projects through an opening (not shown) in the head channel 20. A baton or wand 38 is suitably connected to the end of the worm shaft 350. When thebaton 38 is manually rotated, it rotates the worm shaft 350 and the worm; the

v worm drives the gear which has the hubs 36a and 36b;

the legs 26b and 26e the base 26a of the-cradle is provided with front and rear holes 26j and 26k which register. with holes (not shown) in the bottom 20c of the head channel and provide passage for the front and rear sidepieces 18a and 18b, respectively, of the ladder and the gear rotates-the tilt bar 24 with consequent tilting of the slats 17 of the blind, all as is well understood.

. in US. Pat. No. 3,425,479, to which reference ismade for more complete disclosure thereof. The head 16 includes, at each end thereof, a sheet-steel end brace B (one shown). Each end brace B is telescoped into and spans the end of the head channel 20. This end brace and its cooperation with the head channel are disclosed in US. Patent 3,425,480, to which reference is made for more complete-disclosure thereof. As will be seen from FIG. 1, the end brace B at the left end of the head, in addition to bracing the end of the head channel 20, acts as a stop which limits longitudinal movement of the tilt bar 24 to the left.

The tilt-limiting attachment shown in FIGS. 24 consists of a limit member which is designated as a whole by 44 and a stop member which is designated as a whole by 50. Each of these two parts is stamped in one piece from heavy gage sheet steel. Sheet steel approximately 0.09 inch thick may be used for the member 44, and sheet steel of lesser thickness may be used for the member 50.

The limit member 44 is disc-like and has a central D- shaped hole 44a which mates with the D-shaped tilt bar 24. Segments of the disc are cut off, leaving chordal edges 44b and 44c which engage the stop member 50 and establish a pair of limits for the tilting of the slats 17 (FIG. 4) as will be explained. With the tilt bar temporarily in the position shown in FIG. 2, thelimit member 44 is telescoped onto the tilt bar 24 as indicated by the arrow headed phantom line 40. The limit member 44 is brought adjacent to the tilter 30, where it is to remain; see FIG. 3. The tilt bar 24 is shifted to the left until its left end is contiguous to the left-hand end brace B; see FIG. 1.

The tilt bar 24 may be temporarily positioned as shown in FIG. 2, andthe limit member 44 applied to the tilt bar, before the right-hand end of the tilt bar has been confined by bending the finger 26f (FIG. 1) over the right-hand end of the tilt bar. Where both ends of the tilt bar 24 have been confined already, as shown in FIG. 1, the finger 26f may be 'bent away temporarily to permit the tilt bar to be shifted to its FIG. 2 position for application of the limit member 44. Alternatively, the

- finger 26f may be left bent across the end of the tilt bar and the left-hand end brace B be removed temporarily to give access to the left end of the tilt bar 24 for the telescoping of the limit member 44 onto the tilt bar.

In some blinds the tilter30 is toward the right-hand end of the head 16, instead of towardthe left-hand end as shown in FIG. 1. In such case removal temporarily of the left-hand end brace B willpermit the tilt bar 24 to be withdrawn from the tilter for telescoping the limit member 44 onto the right-hand end of the tilt bar 24 after which the tilt bar 24 is reengaged with the tilter and the limit member 44 positioned adjacent to the left side of the tilter.

The stop member 50 has a channel-shaped body that extends vertically for embracing the rear of the tilter housing. The channel formation of the body has a wide bottom 50a and Iowside-walls 50b-and 50c. Toward its top end the bottom wall 50a isprovided with a transversely elongated opening 50d, from near one end of which a slit 50e extends downwardly. This provides a tab of metal which has a horizontal free-edge at the top of the tab and a depending free-edge at the'slit 50e.

This tab of metal is bent rearwardly, providing a latch 50f; see also FIGS. 3 and 4. At an upper level on the stop member 50 there is an offsetting portion 50g which extends to the left from the free edge of the side 50b; This offsetting portion 50g integrally supports a hook:shaped retainer portion 50h.

To provide ample clearance for the entry of the tilter 30 into the head channel 20, the longitudinal flanges or edges 20d are locally collapsed at 20h; see particularly FIG. 4. When the tilter has been installed, this leaves space between the back of the tilter housing and the inturned rear'edge of the head channel 20.-The stop member 50 is inserted downwardly into this space, as indicated by the vertical phantom lines extending from the stop member 50 in FIG. 2. The body-portion part 50a of the stop member is then between the tilter housing and the rear wall 20b of the head channel, as is seen in FIGS. 3 and 4. The side walls 50b and 500 of the body of the stop member50 extend alongside the two sides of the tilter which face toward the two ends of the head channel, respectively. The latch 50f snaps beneath the edge portion 20h of the rear inturned flange of the head channel 20, thereby securing the stop member'50 in the position shown in FIGS. 3 and 4 in which position the bottom end of the stop member 50 is against the-bottom wall 20c of the head channel and the top end of the stop member 50 is at a level that is close to the top of the tilter 30. The hook portion 50h straddles the tilt bar 24 and, as seen in FIGS. 4 and 3, is disposed in a vertical plane alongside the limit member 44 and retains the limit member 44 adjacent to the tilter.

The parts are so proportioned as to provide the clearances appropriate for application of the stop member 50 to the head 16 as just described and, at the same time, obviate objectionable looseness of the applied stop member '50.

The limit member 44 establishes a pair of tilting limits for the slats 17 (FIG. 4), i.e., a limit for forward tilt of the slats and a limit for rearward tilt of the slats For the particular limit member 44 that is shown in FIGS. 2-4 these tilting limits are each 45. Upon the slats being tilted forwardly (front edges depressed) and reaching a forward tilt of 45, the chordal edge 44b of the limit member 44 strikes the bottom edge of the offset 50g of the stop member. This terminates the tilting movement at 45 of forward tilt of the slats 17. Upon the slats being tilted rearwardly (front edges elevated) and reaching a rearward tilt of 45, the chordal edge 440 of the limit member 44 strikes the offset 503. This terminates the tilting movement at 45 of rearward tilt of the slats 17.

The stop member 50 may be unlatched readily from the head channel by inserting the tip of a screw driver into the hole 50d and springing the inturned edge 20h of the head channel out of holding engagement with the latch 50f. The prying action of the screw driver will start the stop member 50 upwardly for facile removal. Then the tilt-limiting member 44 may be removed by procedure which is the reverse of that used in applying it to the tilt bar .24. Thus the blind may be restored to full slat tilting of nearly in each direction. Alternatively, the particular limit member 44 may be replaced by a similar limit member which, however, establishes a different pair of tilting limits for the slats 17.

FIGS. 5-11 show seven tilt-limiting members which are designated from 41 to 47, respectively. The limit' member 44 of FIG. 8 is the particular limit member that is shown in FIGS. 2-4. The limit member 41-47 I may be used interchangeably to establish different pairs of tilting limits for the slats 17 as may be desired. Each of FIGS. 5-11 shows, in the center of the figure, the limit of forward tilt of the slats this limit being 0 in FIGS. 9 and 10. Each of FIGS. 5-11 shows, in the righthand portion of the figure, the limit of rearward tilt of the slats this limit being 0 in FIG. 5. It will be understood that, in addition to the seven specific limit members 4147 that are shown, other limit members may be used to provide still other specific pairs of limits.

For practical purposes the limits of tilt indicated in FIGS. 5-11 maybe considered to be approximate. Ordinarily the tilt limiting requirements are only approximate, and there is no need to resort to precision manufacture of parts to hold the actual tilts very close to the nominal tilting-limits.

. t 7 What is claimed is: l. A Venetian blindwhich has a head that includes (1) an elongated channel that has a bottom wall and upstanding front and rear walls, -(2) a tilter mounted within the channel, and (3) a tilt bar which extends longitudinally within the channel and is rotated back and forth by the tilter", the ladder-and-slat assembly of the blind being supported from thetilt bar, and rotative movement of the tilt bar being transformed into tilting movement of the slats wherein the improvement comprises: an attachment which limits the tilting movement of the slats to an amount that is less than the tilting movementafforded by the tilter itself, said attachment comprising (a) a stop member which is applied to the head and (b) a cooperating limit member which is applied to the tilt bar of the head and rotates into engagement withthe stop member and arrests the rotation of the tilt bar before the slats have been tilted, in

one or both directions, to the degree of tilt afforded by the tilter itself.

2. A Venetian blind as in claim 1 wherein the im- 7 provement further comprises:

the attachment is removable readily to restore the available tilting movement of the slats to the full tilting movement afforded by the tilter itself. 3. A Venetian blind as in claim 1 wherein the improvement further comprises:

the limit member which is applied to the tilt bar is replaceable readily'with 'a limit member which provides-a different limit of tilt of the slats. in one or both directions. 4. A Venetian blind as in claim 1 wherein the improvement further comprises: the limit member of the attachment is adjacent to the tilter, and the stop member of the attachment has a body portion which is between the tilter and one of the upstanding walls of the channel. 5. A Venetian blind as in claim 1 wherein the improvement further comprises:

the limit member of the attachment is telescoped onto the tilt bar and makes noncircular confronta- 'tion therewith to cause the limit member to rotate with the tilt bar, the limit member is adjacent to the tilter, and the stop member of the attachment has a portion which extends alongside the limit member and retains the'limit member adjacent to the tilter. 6. A Venetian blind as in claim I wherein the improvement further comprises: 7

the limit member of the attachment is adjacent to the tilter, I the stop member of the attachment has a body portion which is between the tilter and the rear wall of the channel, and the stop member has body portions that extend alongside the two sides of the tilter which face toward the two ends of the channel, respectively.

7. A Venetian blind as in claim 1 in which the upper edges of the channel are inturned and wherein the improvement further comprises: i

the stop member of the attachment is provided with a latch which engages beneath one of the inturned edges of the channel and thereby latches the stop member to the head of the blind.

8. A Venetian blind as in claim 7 wherein the improvement further comprises:

the stop member of the attachment. is removable from the head by springing the inturned edge of the channel out of holding of the stop member.

9. A Venetian blind as in claim 8 wherein the improvement further comprises:' i

the limit member of the attachment is telescoped onto the tilt bar and makes noncircular confrontation therewith to cause the limit member to rotate with the tilt bar,

the limit member is adjacent to the tilter,

and the stop member of the attachment has a portion which extends alongside the limit member and retains the limit member adjacent to the tilter.

engagement with the latch 

1. A Venetian blind which has a head that includes (1) an elongated channel that has a bottom wall and upstanding front and rear walls, (2) a tilter mounted within the channel, and (3) a tilt bar which extends longitudinally within the channel and is rotated back and forth by the tilter; the ladder-and-slat assembly of the blind being supported from the tilt bar, and rotative movement of the tilt bar being transformed into tilting movement of the slats - wherein the improvement comprises: an attachment which limits the tilting movement of the slats to an amount that is less than the tilting movement afforded by the tilter itself, said attachment comprising (a) a stop member which is applied to the head and (b) a cooperating limit member which is applied to the tilt bar of the head and rotates into engagement with the stop member and arrests the rotation of the tilt bar before the slats have been tilted, in one or both directions, to the degree of tilt afforded by the tilter itself.
 2. A Venetian blind as in claim 1 wherein the improvement further comprises: the attachment is removable readily to restore the available tilting movement of the slats to the full tilting movement afforded by the tilter itself.
 3. A Venetian blind as in claim 1 wherein the improvement further comprises: the limit member which is applied to the tilt bar is replaceable readily with a limit member which provides a different limit of tilt of the slats in one or both directions.
 4. A Venetian blind as in claim 1 wherein the improvement further comprises: the limit member of the attachment is adjacent to the tilter, and the stop member of the attachment has a body portion which is between the tilter and one of the upstanding walls of the channel.
 5. A Venetian blind as in claim 1 wherein the improvemeNt further comprises: the limit member of the attachment is telescoped onto the tilt bar and makes noncircular confrontation therewith to cause the limit member to rotate with the tilt bar, the limit member is adjacent to the tilter, and the stop member of the attachment has a portion which extends alongside the limit member and retains the limit member adjacent to the tilter.
 6. A Venetian blind as in claim 1 wherein the improvement further comprises: the limit member of the attachment is adjacent to the tilter, the stop member of the attachment has a body portion which is between the tilter and the rear wall of the channel, and the stop member has body portions that extend alongside the two sides of the tilter which face toward the two ends of the channel, respectively.
 7. A Venetian blind as in claim 1 in which the upper edges of the channel are inturned and wherein the improvement further comprises: the stop member of the attachment is provided with a latch which engages beneath one of the inturned edges of the channel and thereby latches the stop member to the head of the blind.
 8. A Venetian blind as in claim 7 wherein the improvement further comprises: the stop member of the attachment is removable from the head by springing the inturned edge of the channel out of holding engagement with the latch of the stop member.
 9. A Venetian blind as in claim 8 wherein the improvement further comprises: the limit member of the attachment is telescoped onto the tilt bar and makes noncircular confrontation therewith to cause the limit member to rotate with the tilt bar, the limit member is adjacent to the tilter, and the stop member of the attachment has a portion which extends alongside the limit member and retains the limit member adjacent to the tilter. 